Air bag contoured for safety

ABSTRACT

An air bag whose envelope is a front panel and a rear panel joined around a common periphery and having a tether having one edge joined to an inside surface of the front panel and another edge joined to the inside surface of the rear surface near the entry port. The tether has two members, an elastic member that is shorter than an inelastic member in its unstretched state. The elastic member controls the rate of inflation of the air cushion thereby lessening the chance of injury due to the sudden inflation of the air bag. The inelastic member controls the shape of the air cushion to accommodate the face and head of the passenger

FIELD OF THE INVENTION

[0001] This invention relates to air bags to prevent injuries fromcrashes to passengers, particularly children, riding in automobiles.

BACKGROUND AND INFORMATION DISCLOSURE

[0002] Air bags in vehicles that expand suddenly in the space betweenthe dash board and passenger when a crash occurs have been shown to bean important means for preventing many deaths or injuries since theiradoption by the automobile industry.

[0003] An ambiguity exists however in the operation of the bag which, onthe one hand, requires great force by the expanding gas in order for thebag to expand very quickly and immobilize the passenger during the splitsecond after the crash, but the passenger must not be injured by theforce driving the rapidly expanding bag.

[0004] The consequence of this ambiguity has been that, although manythousands of drivers and passengers have been saved from injury anddeath by deployment of air bags, some passengers and especiallychildren, have been killed when these bags have been deployed.

[0005] A number of disclosures have appeared related to the variousdesigns of air bags intended to address the problem of air bag designespecially devoted to the protection of children.

[0006] For example, U.S. Pat. No. 57168995 to Lopez discloses a child'sseat for an automobile in which a safety shield attached to the seat ispositionable in front of the child to protect against the force of thesuddenly expanding bag.

[0007] U.S. Pat. No. 5,884,939 to Yamaji discloses an air bag having adiffuser that controls rate of expansion of the bag.

[0008] U.S. Pat. No. 5,895,092 to Fischer discloses a child's car seatwith an air bag protection bar.

[0009] U.S. Pat. No. 5,924,726 to Pan discloses an air bag packagedesigned in combination with a safety belt.

[0010] U.S. Pat. No. 5,931,498 to Keshavaraj discloses an inflatable airbag comprising two sections. One section is constructed with a pyramidalpanel and the other section is constructed with a rectangular panel. Thesections are joined and configured to conform to the shape of the dashboard. U U.S. Pat. No. 5,957,485 to Hirai discloses an air bag structureincluding an outer bag having an internal cavity and an inner bagdisposed in the cavity.

[0011] The problem with these examples of the prior art is that, whendeployed and in use for their intended purpose, they over extend thesafe distance for contact with the human face and body.with a force thatthreatens the safety (and life of the individual it is intended toprotect. None of these disclosures accommodate the condition where thebag must protect various parts of the anatomy, each having its ownrequirements for protection. in terms of the distribution of mass of thebody vs. restraining force of the bag.

SUMMARY OF THE INVENTION

[0012] It is an object of this invention to provide an air bag whosedynamic action in terms of force and rate of displacement vary invarious parts of the bag in order to accommodate parts of the passengersbody that come in contact with the bag.

[0013] It is an object that the bag be adapted to the protection ofchildren.

[0014] This invention is directed toward an air bag having an internalcheckrein restraining construction that shortens the extent of theforward movement of the bag the air bag is deployed by a crash. Thecheck rein construction comprises (in one embodiment) a front panel andrear panel, and are joined round their common periphery. The panels layagainst one another when the bag is fully deflated. A tether inside thebag has one edge secured to an inside surface of the front panel and anopposite edge secured to the inside surface of the rear panel.

[0015] When fully inflated, the air bag of this invention assumes abulbous shape with a concavity in its center so that the air bag “Wrapspartially around the head and body as the air bag is deployed. The shapeof the inflated bag including the concavity is selected according to theshape of the body or object (e.g., a small child) it is intended toprotect.

[0016] In one embodiment, the tether has an elastic component thatcontrols not only the rate and extent of expansion of the central areaof the bag facing the face of the user, but also the rate of expansionof the peripheral areas of the bag.

[0017] The various features, aspects and advantages of the presentinvention will become better understood with regard to the followingdescription, appended claims, and accompanying drawings, where

BRIEF DESCRIPTION OF THE DRAWINGS

[0018]FIG. 1 is a perspective assembly view of the air bag.

[0019]FIG. 2 is a sectional view of FIG. 1.;

[0020]FIG. 3 is a view with the top panel removed.

[0021]FIG. 4 is a sectional view of a partially inflated air bag of thisinvention.

[0022] FIGS. 5A-D illustrate action of the composite tether.

[0023]FIG. 6 shows an embodiment featuring vertical deployment of thebag.

DISCUSSION OF EXAMPLES OF THE INVENTION

[0024] Turning now to a discussion of the drawings, FIG. 1 shows aperspective assembly view of the inflated air bag of this invention andFIG. 2 is a sectional view of FIG. 1. There are shown an envelope 10having an inside containing a tether 16. The envelope comprises a rearpanel 12 joined to a front panel 14 around a common periphery 15. Thetether 16 is shown which in the example of FIG. 1 is a pair of straps 16shown in phantom in fig, 1. Each strap has one end secured to the insidesurface of the rear panel 12 and another end secured to the insidesurface of the front panel. 14.

[0025]FIG. 3 is a cutaway perspective view (the front panel is cut away)showing another embodiment in which the tether is a disk 20 of material,sewn around its outer periphery 22 to the front panel 14 (front panel 14is partially cutaway in FIG. 3) and around its inner periphery 23 to therear panel 12. The tether is shown as a cone 20 in FIG. 3 because thebag has been inflated however, when the bag is deflated, the tether willbe flat inside the bag.

[0026] The gas is generated by an inflater 13 and admitted into the bagthrough the central opening in the disk and rear panel. Inflatertechnology for generating gas under pressure is well known in the art ofsafety air bags for automobiles.

[0027]FIG. 4 is a sectional view showing the bag partially deflated andthe tether 20 partially folded.

[0028] FIGS. 5 A-D are sectional views illustrating a construction ofthe tether, applicable to either a strap, disk or other configuration ofthe tether for controlling the rate of expansion of one area of the Airbag (the center) relative to another area of the air bag. The tether hasan elastic member 24 and an inelastic member 26.

[0029] In the context of this specification, the term “extended”. and“extending” will be applied to both members when the ends of therespective members are being separated. The elastic member will be saidto be “fully extended” when the ends of the elastic member are separatedby the maximum distance before stretching occurs. The term stretchedwill describe the elastic member when the ends of the elastic memberhave been displaced by a di stance greater than the fully extendedcondition.

[0030]FIG. 5A shows the tether in a condition when the air bag ispartially inflated. The over all length of the inelastic member 26 isgreater than the length of the elastic member 24.

[0031] As gas enters the bag, FIG. 5B shows the elastic member 24extended to its full unstretched length. The inelastic member 26 has notbeen fully extended. At this point, the surface of the bag hasapproached the face of the passenger at a relatively unlimited speed.

[0032] As shown in fig. SC, continued inflation causes the elasticcomponent 24 to stretch to a full limit where the inelastic componentreaches its fullest extension. During this time of stretching theelastic component 24, the elastic component slows down rate of expansionof the central portion of the bag thereby reducing the eventual force ofimpact against the face of the passenger and increasing the rate atwhich the outside area of the air bag wraps around the body and head ofthe passenger.

[0033] As shown in FIG. 5D, when the inelastic component 26 reaches thelimit of its extension, the only change in shape due to the expansion ofthe air bag will be the continued extension and wrapping around the head27 and body of the outside regions 29 of the bag. There will be no forceagainst the face of the passenger except the impulse generated by themomentum change of the head and this impulse will be dampened by thecushion properties of the air bag.

[0034] The principles of bag construction of this invention may beapplied to a system that relies on horizontal deployment of the bag suchas when the folded bag is stored adjacent the vizor overhead thepassenger or deployed horizontally such as when the bag is stored in thesteering column or dashboard of the car.

[0035] For example, FIGS. 1-5 show air bag configured for horizontaldeployment. The gas inlet 31 is in the center of the bag and gas entersthrough an aperture in the center of the bag as discussed above.

[0036]FIG. 6 is a sectional view showing the bag configured for verticaldeployment in which case the bag is suspended and gas is admitted at theperiphery of the panels but the tether is still located in the center ofthe panels as discussed above.

[0037] While the bag has been described above as an envelope comprisinga front panel and rear panel joined at a common periphery with thetether attached to the approximate center of the panels, it will beunderstood that that the envelope may be constructed as a singleintegral piece (such as a balloon

[0038] While the drawings and discussion above have shown a elasticmember distinct from an inelastic member, it should be understood thethe equivalent of a two member (elastic and inelastic) comprises afabric composed of elastic thread and inelastic thread where theinelastic thread is longer than the elastic thread.

[0039] There has been described an air bag that features shape anddynamic characteristics conducive to the protection of the passengerduring the crash of a vehicle in which the passenger is riding.

[0040] Variations and modifications and modifications of the inventionmay be contemplated which are within the scope of the invention.

[0041] For example, in place of a disk or strap, the tether may be arectangle and the panels of the air bag may be rectangular or otherconvenient shape depending on the requirement of the outer edges of theexpanded bag to conform to the conformation of the door, dash boardand/or ceiling of the interior of the automobile.

[0042] The shape of the air bag when expanded determined by theconstruction of the tether, may have any one of a number of shapesdepending on the object to be protected, particularly children, adultsor objects of value.

[0043] In one embodiment, the principles of the bag construction isapplied to a bag designed specifically for vertical or horizontaldeployment.

[0044] In one embodiment, the elastic part of the tether is any one of anumber of elastomeric materials such as rubber, neoprene, or urethane.

[0045] In one embodiment, the inelastic component of the tether is anyone of a number of materials including cotton or other vegetable fibermaterial impregnated with a coating to render the bag air tight, leatheror plastic sheet such as acetate, vinyl, nylon, polyethylene, etc. orcombinations thereof.

[0046] In view of these and other considerations prompted by reading thespecification and studying the drawings that are within the scope of theinvention, it is therefore wished to define the scope of this inventionby the appended claims.

What is claimed is:
 1. An inflatable air bag attachable to an inflaterfor deployment in an automobile for the protection of passengers, saidbag comprising: an envelope having an entry port for admitting gas. atether having an edge; said tether positioned inside said envelopehaving one length of said edge secured to an inside surface of saidenvelope at one location and another length of said edge secured to saidinside surface at another location of said edge; said one location andsaid another location operably selected in combination with a dimensionof said tether to form a concavity in said surface of said envelopearranged to increase protection of said passenger when said bag issuddenly inflated; said envelope adapted to being secured to an inflaterand communicating with said inflater through said entry port.
 2. Theinflatable air bag of claim 1 wherein: said envelope is a flexible rearpanel and a flexible front panel joined together around a commonperiphery; said entry port is located about in a center of said rearpanel; said tether is at least one strap, each said at least one straphaving one end joined to an inside surface of said front panel andanother end joined to an inside surface of said rear panel proximal tosaid entry port; each said at least one strap having a length selectedto provide that when said envelope is inflated through said entry port,said strap limits expansion of said envelope whereby a concavitycentrally located in a center of said front panel is formed.
 3. Theinflatable air bag of claim 1 wherein: said envelope is a flexible rearpanel and a flexible front panel joined together around a commonperiphery; said entry port is located about in a center of said rearpanel; said tether is a tether panel of flexible material having anouter boundary and a centrally located aperture defined by an innerboundary; said outer boundary attached to an inside surface of saidfront panel and said inner boundary joined to an inside surface of saidrear panel and surrounding and proximal to said entrance port; saidtether panel having a plurality of openings permitting gas to enterevery region inside said envelope. said tether panel having a sizeselected to provide that when said envelope is inflated through saidentry port, a concavity centrally located in a center of said frontpanel is formed.
 4. The inflatable air bag of claim 1 wherein saidinflater is installable in one of a steering column and a glovecompartment of said automobile and said envelope is adapted to providethat, when said air bag is fully inflated, a length of an edge of saidperiphery of said envelope lies substantially against an inside surfaceof a door of said automobile and a front surface of said envelope isforced against said passenger sitting in said car adjacent said door. 5.The air bag of claim 1 wherein said envelope is made of a sheet ofmaterial selected from a group of materials that consists of an airproof vegetable fiber cloth and a plastic sheet.
 6. The air bag of claim1 wherein said tether is a composite comprising an elastic member aninelastic member; said elastic member and inelastic member having acommon end secured to said one location and another common end securedto said another location; said elastic member having a length that isshorter than a length of said inelastic member providing that when saidair bag is deflated, both said inelastic and elastic members areunextended, and when gas initially enters said bag, said elastic memberwill first extend until said elastic member is fully extended, and, assaid bag continues to inflate, said elastic member will stretch and saidinelastic member will extend until said inelastic member is fullyextended whereby an area of said bag adjacent said second location willcease to unfold while areas of said air bag distal from said secondlocation contnue to unfold providing that a concavity is formed in saidexpanded air bag.
 7. The air bag of claim 6 wherein: said tether is atleast one strap; each said at least one strap including an elastic strapand an inelastic strap; said inelastic strap being longer than saidelastic strap; said inelastic strap and said elastic strap having onecommon end joined at said first location and another common end joinedat said second location.
 8. The air bag of claim 7 wherein saidinelastic strap is made of material selecting from a group of materialsconsisting of vegetable fiber cloth impregnated with an air tightcoating and a plastic sheet and said elastic strap is made of materialselected from a group of materials consisting of rubber, neoprene,urethane. 9 The air bag of claim 1 wherein said envelope comprises: apair of panels joined around a common periphery; said entry port isproximal to a location on said periphery; said one location where oneedge of said tether is secured is about in the center of one said paneland said another location where another edge of said tether is securedis about in the center of said other panel. providing that, when saidair bag is inflated from a ceiling and over a seat of said vehicle, saidair bag unfolds in front of said seat with concavity formed locatedadjacent a face of an occupant of said seat.
 10. 1. An inflatable airbag attachable to an inflater for deployment in an automobile for theprotection of passengers, said bag comprising: an envelope having anentry port for admitting gas. said envelope being a a rear panel and afront panel joined around a common periphery of said front and rearpanels; a tether being one of: (i) at least one strap, each one of saidat least one strap having one end secured to said front panel near acenter of said front panel and another end secured to said rear panelnear a center of said rear panel and near said entry port; (ii) a tetherpanel having an opening positioned in about a center of said tetherpanel and with an outer edge secured to an inside surface of said frontpanel and an edge of said opening secured to an inside surface of saidrear panel around said entry port; said tether comprising an elasticmember and an inelastic member joined where edges of said elastic andinelastic members are secured to said front and rear panels; saidelastic member being smaller than and inelastic member such that, whensaid air bag is being inflated, said elastic member will be fullyextended and then as said air bag is further inflated, said elasticmember is stretched until said inelastic member is fully extended. 11.The air bag of claim 1 wherein: said tether is a composite fabriccomprising elastic threads interwoven with inelastic threads; saidelastic threads, when unstretched<having a length that is shorter than alength of said inelastic threads providing that when said air bag isdeflated, both said inelastic and elastic threads are unextended, andwhen gas initially enters said bag, said elastic threads will firstextend until said elastic thread is fully extended, and, as said bagcontinues to inflate, said elastic threads will stretch and saidinelastic threads will extend until said inelastic threads is fullyextended whereby an area of said bag adjacent said second location willcease to unfold while areas of said air bag distal from said secondlocation continue to unfold providing that a concavity is formed in saidexpanded air bag.